Cannot Ping Gateway IP Address on Linux

[Jagdish Gada]

hi there

I am having some problem with my linux operating ssystem. I am able to ping my wireless routers IP address but cannot get the gateway IP address?

When I try to ping the IP address I get the Reply from 192.168 and everything is fine. but when I ping the gateway IP address i get Destination Host Unreadable. I have tried everything I can think of but to no solution.

Please help me regarding this problem

your views will be appreciated

[Solomon]

I believe that this is a non-functional default address that is set only temporarily until for example a DHCP server sets the final address.

Maybe there is a DHCP server that haven't been started properly or somethimg like that.

Another question is the netmask. The last byte 240 (= 1111 0000) isn't a bit restrictive?

You could check the arptables of each box with "arp -en" to see what other connection each box sees. That is sometimes helpful to get a clue when ping and arpings are failing for no apparent reason.

[MrChris-]

I think it would need to see x.x.x.32 as your gateway (properly configured what I'm not sure) to be able to see x.x.x.33.

To get a picture of your LAN, you get on every computer, run "ifconfig" and compare IP address and HWaddress (= MAC address) with the figures from "arp -en". You can run "arp -en" on these computers as well.

Now, "arp -en" says that there are 3 computers in your LAN.

This arp table is populated by arpings. Every time you send a new ping after some time, the network launches implicitely an arping before that. That arping matches IP addresses with Ethernet MAC addresses, because the Ethernet protocol doesn't know the IP protocol and works only with MAC address.
A subsequent ping then looks up the arp table to know to which MAC address to send the Ethernet packets when only the IP address is given.

[Calvin K]

do you have a DHCP server running? if so, try setting your linux box to obtain an ip address. if not, make sure your drivers for the nic are installed correctly.

you can vist this link for further information:

http://newbiedoc.sourceforge.net/net...megateway.html

[Lillebror]

1.Ping a host on your TCP/IP subnet by hostname. If the ping fails, ping that host by IP address. If the ping still fails, you know that TCP/IP connectivity is down, at least for your workstation; if it fails on the host name attempt but works by IP address, you know that name resolution isn’t functioning properly.

2. If the host responded properly when pinged by hostname, ping the gateway address. If it replies, you know your gateway is alive; if not, you may have any of number of problems communicating with your gateway device, including incorrect subnet mask and/or gateway address configuration, a polluted ARP (Address Resolution Protocol) cache, or a gateway that’s simply down.

3. If your gateway responds, ping a host on another local subnet, if available. If that host replies, you know your intranet is functioning; if not, you may have connectivity problems between gateway or between ports on the same gateway.

4. Ping your intranet gateway to the Internet. If it responds, you Internet gateway is alive; if not, you have probably isolated your problem.

5. Ping various host on Internet. This enables you to detemine how localized you connectivity failure is.

Traceroute (or Tracert, as the tool is named under Windows). You initiate a traceroute by running the program and passing it the name of the destination host. Every TCP/IP connection between yourself & that host is tested to ascertain both network connectivity & response time. The Traceroute uitility send a special traceroute package to the firts upstream host (normally your TCP/IP gateway), listing the destination of the traceroute. That forst upstream host, if alive, responds to the originator by sending the equivalent of a ping response, with a confirmation of receipt, and forwards the traceroute packet on the next upstream host. This process continues until the destination is reached or the TTL for yje tracetoute packet is exceeded.

Like Ping, The Traceroute utility has a number of cinfiguration options. Traceroute is extremely useful for isolating the point of the network failure, because it can shoe which gateway device is not responding and even reveal whether one port on a gateway device is dead. Traceroute can also show you, with the response time statistic for each response, where network slowdowns are taking place. When used in combination, Traceroute & Ping are, perhaps, the most valuable software tools available to the adminstartor of the TCP/IP network.